Sixty six million years ago, the sudden extinction of the dinosaurs started the ascent of the mammals, ultimately resulting in humankind's reign on Earth. Climate scientists now reconstructed how tiny droplets of sulfuric acid formed high up in the air after the well-known impact of a large asteroid and blocking the sunlight for several years, had a profound influence on life on Earth. Plants died, and death spread through the food web. Previous theories focused on the shorter-lived dust ejected by the impact. The new computer simulations show that the droplets resulted in long-lasting cooling, a likely contributor to the death of land-living dinosaurs. An additional kill mechanism might have been a vigorous mixing of the oceans, caused by the surface cooling, severely disturbing marine ecosystems according to Science daily.